Simulation and measurement of road tunnel ventilation

A computer program forPC has been prepared to simplify studies of air flows in road tunnels and the related problem of pollution concentration due to emission from vehicles. Results from simulations include air pressures, flow rates, and pollution concentrations along the tunnel. Input data are tunnel geometry, including flow friction factors and loss coefficients, plus traffic and emission data and air pressures at boundaries. The program has been prepared in the IDA environment for modular simulation. All mathematical models have been formulated in the Neutral Model Format (NMF) [Sahlin 19941. The program has been validated by comparisons with older programs (Malmstrom 1980). Advantages of the new program, as compared to traditional programs, are its great flexibility, ease of maintenance, and extendibility, as well as the very moderate implementation time. It has proved to be a useful tool for studying alternative ventilation concepts for road tunnels. Air flow rates have been measured in part of the “Södersledstunneln,” a much-used road tunnel in central Stockholm. The measurements were made with tracer gas technique, which made it possible to measure without disturbing the traffic flow through the tunnel. The measurements have been compared to simulations of the air flow.     

Tissue, age, and sex distribution of thallium in shrews from Doñana, a protected area in SW Spain

In 1998, the protected area of Do?ana, an important natural region in SW Europe, was affected with great amount of acidic waters and sludge from a pyrite mine loaded with toxic metals such as thallium (Tl). Since this ecological catastrophe, several studies have addressed the effects of this pollution on the flora and fauna in this protected area. However, in contrast to other non-essential metals, scarce information on Tl was available after this disaster, especially in terrestrial environments. This study reported a 3- and 10-fold increase in Tl in liver and kidneys, respectively, of the greater white-toothed shrew, Crocidura russula, in the polluted site in comparison with reference animals. Kidneys showed the highest concentrations of this metal in the polluted site, whereas both organs analysed have similar concentrations in the reference site. Although no significant age-dependent variation was found, adults had higher concentrations than juveniles. Moreover, females showed higher concentrations than males. These results demonstrate the high entrance and transfer of Tl in terrestrial food-chains. To the best of my knowledge, these data constitute the first measurements of Tl in mammals from the protected area of Do?ana and are among the few available for insectivorous mammals.     

公路隧道照明节能的形势和对策

当前我国公路隧道照明能耗严重,存在的突出问题是照明系统设计超标、照明控制方式落后、照明节能理念有误、照明节能措施单一。以建设"资源节约型、安全环保型"公路隧道为出发点,从宏观层面分析公路隧道照明节能的五大关键环节,并从系统工程角度提出公路隧道照明节能的对策:技术性、结构性、管理性节能。工程实践表明,公路隧道运营照明节能20%以上的目标是完全能够实现的,可产生显著的经济、生态和社会效益。     

现代公路隧道安全管理初探

我国公路建设迅速发展,公路隧道不断增加。由于处于封闭的环境中,隧道中一旦发生事故,特别是火灾,往往导致严重的人员伤亡和财产损失。因此隧道安全管理问题是面临的一个重要课题。在调查国内外相关研究资料的基础上,对公路隧道的安全管理方法进行了归纳总结,以便为我国公路建设和维护管理提供参考。     

Chemical and ecological effects of contaminated tunnel wash water runoff to a small Norwegian stream

Cleaning and washing of road tunnels are routinely performed and large volumes of contaminated wash water are often discharged into nearby recipients. In the present study, traffic related contaminants were quantified in tunnel wash water (the Nordby tunnel, Norway) discharged from a sedimentation pond to a nearby small stream, Årungselva. In situ size and charge fractionation techniques were applied to quantify traffic related metal species, while PAHs were quantified in total samples. All metals and several PAHs appeared at elevated concentrations in the discharged wash water compared with concentrations measured in Årungselva upstream the pond outlet, and to concentrations measured in the pond outlet before the tunnel wash event. In addition, several contaminants (e.g. Cu, Pb, Zn, fluoranthene, pyrene) exceeded their corresponding EQS. PAH and metals like Al, Cd, Cr, Cu, Fe and Pb were associated with particles and colloids, while As, Ca, K, Mg, Mo, Ni, Sb and Zn were more associated with low molecular mass species (< 10 kDa). Calculated enrichment factors revealed that many of the metals were derived from anthropogenic sources, originating most likely from wear of tires (Zn), brakes (Cu and Sb), and from road salt (Na and Cl). The enrichment factors for Al, Ba, Ca, Cr, Fe, K, Mg and Ni were low, suggesting a crustal origin, e.g. asphalt wear. Based on calculated PAH ratios, PAH seemed to originate from a mixture of sources such as wear from tires, asphalt and combustion. Finally, historical fish length measurement data indicates that the fish population in the receiving stream Årungselva may have been adversely influenced by the chemical perturbations in runoffs originating from the nearby roads and tunnels during the years, as the growth in summer old sea trout (Salmo trutta L.) in downstream sections of the stream is significantly reduced compared to the upstream sections.     

公路隧道穿越煤矿采空区的安全控制措施研究

结合相关实例,分析了公路隧道穿越煤矿采空区的安全隐患,并提出了相应的安全防护措施,指出穿越采空区施工安全管理的注意事项,以期实现道路隧道的安全施工。     

Brandschutz bei Tunneln

Fire Safety for Traffic Tunnels Research and Application The tragic tunnel fires of the past years have lead to discussions of experts in Europe and around the world. In many European countries they have caused a complete revision of the national safety guidelines for road and rail tunnels. The European Commission has developed directives concerning the minimum safety equipment of road tunnels as well as of railway tunnels. This action is supplemented by intensive domestic and international research activities. The findings gained by this are used for design and execution of new road‐and railway tunnels. This is valid especially also for extremely long railway tunnels as for example the Brenner‐Base‐Tunnel.     

Arsenic pollution at the industrial site of Reppel-Bocholt (north Belgium)

An industrial site, polluted with As and heavy metals, was investigated by combining chemical (sequential extractions and pHstat leaching tests), physical and mineralogical characterization of soil samples and slag fragments, and by the analysis of soil porewater aimed at assessing the distribution, speciation and mobility of heavy metals and As. On the site itself, arsenic concentrations up to 3.6% in surficial soil samples and up to 22% in slag fragments were found, together with elevated concentrations (percentage level) of Cu, Co, Ni, Zn and Pb. High concentrations of arsenic (up to 38,000 microg/l) and heavy metals (up to 1700 microg/l Cu and 4700 microg/l Zn) were also found in the in situ sampled soil porewater, highlighting the considerable availability of As, Zn and Cu for uptake by plants and leaching to the ground water. Sequential extractions also indicated a high availability of arsenic and copper in most samples and slag fragments of the industrial site, although poorly reactive phases were encountered as well. pHstat leaching tests confirmed that the present leaching of contaminants is alarming. Moreover, soil acidification will enhance the leaching of contaminants, emphasizing that remediation of the industrial site is urgent. Small scale variability of total metal concentrations and metal speciation, both in the horizontal and vertical direction, and the occurrence of a camouflage layer underline the importance of elaborate sampling for pollution assessment on an industrial site.     

公路路面径流水污染与控制技术探讨

结合国内外研究成果 ,对公路路面径流中主要污染物及其来源、路面径流水质特征、影响路面径流污染的因素 ,及常用路面径流污染控制措施进行了综合分析。认为公路路面径流水质变化很大 ,污染强度较高 ,主要污染物为 SS和 COD,其平均浓度超过污水排放限值 ,在对水质有较高要求的水域路段 ,应通过非工程措施和工程措施的综合实施来实现污染控制。非工程措施主要包括加强公路运输管理、路面清扫、限制除冰剂的使用等 ;工程措施包括植被控制、湿式滞留池、渗滤系统及人工湿地系统等 ,在实际工程应用中 ,可将几种方法组合使用。     

道路与交通对城市生态环境的影响和防治措施

研究分析了道路交通在建设和运行阶段对自然和环境的影响。论述了生态型城市建设中道路交通废气、噪声和粉尘的污染与控制对策;道路交通对动植物、水系、土壤与植被、水土流失、景观环境的影响和保护措施。     

基于数值模拟的北京地区地下道路立交隧道围岩变形分析

城市地下道路立交隧道施工过程中围岩变形分析是工程建设中的核心问题。依托北京城市地下道路工程,采用城区地质条件分层概化方法、三维数值模拟方法分析了临时仰拱台阶法（台阶法）、中隔壁法（CD法）、交叉中隔壁法（CRD法）和双侧壁导坑法（双侧壁法）施工影响下的立交隧道地表沉降、洞周变形和塑性区分布特征,明确了立交区域上下层隧道施工的影响规律。研究发现,立交区域同时受到了上下层隧道施工的影响,在地表形成椭球形的沉降盆,在洞周出现了较大的差异沉降|在地表地层和洞周拱脚、拱肩截面的“X”形区域出现了较为集中的破坏区|CRD法和双侧壁法在控制立交隧道地层变形和破坏方面具有明显优势。研究成果可为北京城市地下道路立交隧道设计、施工决策制定提供参考。     

Effects of forest cover and topographic factors on TOC and associated metals at various scales in western Scotland

Studies at the stream catchment scale have yielded inconclusive evidence of the effects of forest land use on the concentrations of organic carbon in drainage waters. The aim of this paper is to examine the effects of forests on carbon in drainage waters at the plot scale by comparing concentrations of total organic carbon (TOC) and associated metals in soil solutions from sites under forest and moorland vegetation. At an upland site in south-west Scotland soil solution TOC, aluminium and iron concentrations varied with land cover. Mean concentrations of all three determinands were at least 1.5 times greater under forest than under moorland, despite considerable spatial and temporal (seasonal) variability. TOC in soil solutions was also found to vary significantly with both relief and altitude. The altitude effect was particularly marked, with an increase of 26 mg x l(-1) x 100 m(-1) increase in altitude found at an upland site in west-central Scotland. There were no differences in chloride, sulphate or base cation concentrations between forest and moorland sites. Differences in aluminium concentrations could not be linked to atmospheric scavenging at the forest sites, but were closely linked to differences in TOC.     

竖井型自然通风公路隧道气流与污染物分布的影响因素研究

本文针对城市竖井型自然通风公路隧道,采用理论与实验相结合的手段,研究建立了全长隧道气流与污染物分布的数学模型.运用该模型,分类研究了不同竖井间距、竖井截面尺寸、交通量、车速和主体长度工况下,隧道内气流与污染物的分布状况.得出了在浅埋竖井型市政公路隧道的修建与运营过程中,降低主体长度与提高车速可有效改善污染物浓度的分布状况.     

Heavy metals in rivers of Latvia

Total heavy metal concentrations in waters and sediments (HNO3 digestible Pb, Cu, Co, Ni, Mn, Zn) and their speciation forms in sediments (exchangeable, carbonate bound, iron-manganese oxide bound, organic matter bound and residual) in major and common small watercourses (31 sampling stations) along their flow in Latvia were determined. The metal loads entering the Baltic Sea from Latvia were calculated. Increased metal concentrations were found only in lower reaches of the largest rivers and locally around known industrial pollution sources. Differences in metal concentrations and loads in rivers from different regions of Latvia were related to natural geochemical processes. Metal speciation analysis showed that the dominant metal species are residual metals and those bound to organic matter. Residual and carbonate-bound metal dominated only in rhitral regions of rivers. The concentrations of exchangeable metals increased below pollution sources.     

Monitoring of the mediterranean sea pollution (med pol) and data quality assurance

The concerted effort to monitor contaminants and to assess pollution in the Mediterranean Sea was agreed upon by the riverine States with a Programme named MED POL, part of the Barcelona Convention signed up in 1975. For near 25 years, this Programme has been the cornerstone of the Mediterranean Action Plan and has been instrumental to develop the capabilities of the countries to measure and assess marine pollution. Through cooperation with the IAEA Marine Environment Laboratory, in Monaco, which has acted as analytical and training centre for MED POL, hundreds of analysts of the Mediterranean region were trained, equipment was installed and assisted, and analytical techniques to measure pesticides, petroleum hydrocarbons, PCBs, heavy metals, organometallic compounds, and radionuclides in marine samples were tested and adopted. Throughout the years a Quality Assurance programme, which included frequent intercomparison exercises and production of marine reference materials, has also been implemented to improve the comparability of the data. Today, near two thirds of the Mediterranean States implement national marine monitoring programmes to assess water quality and contaminant concentrations. Results of the MED POL programme were embodied in the adoption by the Mediterranean countries of anti‐pollution measures (e.g., emission standards and/or water quality criteria related with mercury, cadmium, radioactive substances, bathing waters, shellfish waters). Trends in marine pollution are shown with data on mussels from the North west Mediterranean and show a reduction of pollutant discharges from land based sources in this area. However, basin wide integrated management of the Mediterranean Sea still requires regional coordinated efforts and increased analytical accuracy in pollution monitoring. The Analytical Quality Assurance has, therefore, a core role in the collaborative assessment of the contamination of the Mediterranean Sea.     

我国城市道路雨水径流污染状况及控制措施

道路是城市汇水面的重要组成部分,也是城市受纳水体非点源污染的主要污染源之一,道路雨水径流污染问题日益引起人们的重视.总结了道路雨水径流污染物成分、来源,对国内外道路雨水径流的EMC进行了对比分析,基于对我国城市道路排水现状的调研分析和部分雨水径流水质数据,对我国几个主要城市道路雨水径流年污染负荷进行了估算,并归纳推荐了一些针对我国道路排水现状的适用性控制措施,同时对我国城市雨水径流污染控制提出了几点建议.     

Major road tunnel projects - How far can we go?

This article considers the main length-limiting elements for road tunnels. Each of the following factors is discussed in terms of the effect of it on road tunnel length: (1) Heading face distance; (2) Site ventilation; (3) Heating-up of the ground; (4) Soil pressures; (5) Risk of inflows under pressure; (6) Deep level geological reconnaissance constraints; (7) Time required for construction; and (8) Construction costs. Other factors are specific to road tunnels: (9) Ventilation and (10) Driver claustrophobia and boredom. The latter factor may eventually be the more restrictive. The conclusion is that none of these factors in and of itself would prevent the construction of road tunnels longer than the Saint-Gothard (16,918m); and that road tunnels may reach 20 km to 25 km. However, only a limited number of sites are available for development of such long road tunnels. Most of the longer road tunnels in the future will be constructed as part of development of huge urban conglomerations to be criss-crossed underground by interwoven networks.     

秦沈客运专线道碴摊铺机的技术改造及底碴摊铺施工

根据秦沈客运专线现场施工及有关的技术要求,结合国外先进经验及实际情况,提出了对德国ABG公司的Titan423摊铺机进行改造的技术措施、注意事项和机械配套情况。可供客运韦线及高速铁路道碴铺设时借鉴。     

巫溪县农村公路水泥混凝土路面结构研究

在对巫溪地区农村公路路基、路面结构和病害现状进行大量调查的基础上,提出了巫溪地区农村公路的分级,制定了各等级农村公路水泥混凝土路面典型结构,供巫溪地区农村公路路面设计应用,对类似山区农村公路路面设计也具有一定参考应用价值.     

Removal of heavy metals from storm and surface water by slow sand filtration: the importance of speciation

The removal of heavy metals from storm and surface waters by slow sand filtration is described. The importance of speciation as a technique for exploring and improving the mechanisms of removal is identified. Laboratory-scale slow sand filters operating at conventional flow rate and depth were shown to be able to reduce concentrations of selected heavy metals (Cu, Cr, Pb and Cd) found in road runoff, surface water and sewage effluents to drinking water standard. Nitrogen, volatile solids and modified Stover speciation were used to differentiate between the potential mechanisms of removal, i.e. active biomass, organic adsorption and simple adsorption or precipitation on the surface of the sand. The data presented show that adsorption via organic ligands was the predominant mechanism for metal removal at the surface of the filter but chemical adsorption was the more important deeper in the filter. In the lower layers the adsorbed metals were more easily exchanged than the organically bound metals. The precise chemical ligands were not identified and varied from metal to metal. The most important operational factors affecting performance were therefore the concentration of organic matter, filter depth and the flow velocity.